In the present study, vibrational frequencies and gauge including atomic orbital (GIAO) 13C-NMR and 1H-NMR chemical shift values of 3‐(2/3/4‐pyridyl)-4‐amino‐1,2,4‐triazole‐5‐thiones in the ground state have been calculated by using the density functional method (B3LYP) with 6-311G(d,p) basis set. The vibrational spectra of the title compounds which is calculated by DFT methods, reproduces vibrational wave numbers and intensities with an accuracy which allows reliable vibrational assignments. The title compounds have been studied theoretically in the 4000–400 cm-1 region and the assignment of all the observed bands were made. In the identification of calculated IR data was used the veda4f program. Theoretical infrared spectrums are formed from the data obtained according to B3LYP method. The calculated IR data of title compounds were calculated in gas phase by using of 6-311G(d,p) basis sets of B3LYP method and are multiplied with appropriate adjustment factors. Also, The 1H- and 13C- nuclear magnetic resonance chemical shifts values of 3‐(2/3/4‐pyridyl)-4‐amino‐1,2,4‐triazole‐5‐thione molecules have been calculated by the gage including atomic orbital (GIAO) method. The calculated 13C-NMR and 1H-NMR chemical shift values compared with the experimental values. Experimental data were obtained from the literature. Furthermore, total static dipol moment (μ), the mean polarizability (<α>), the anisotropy of the polarizability (Δα), the mean first-order hyperpolarizability (<β>), of title compounds have been investigated by using B3LYP levels with the 6-311G(d,p) basis set.
1 2 4‐Triazole‐5‐thione, GIAO, B3LYP, Polarizability, Hyperpolarizability